null_value.cc

// Copyright 2023 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "google/protobuf/struct.pb.h"
#include "absl/base/nullability.h"
#include "absl/log/absl_check.h"
#include "absl/status/status.h"
#include "absl/strings/cord.h"
#include "common/value.h"
#include "internal/status_macros.h"
#include "internal/well_known_types.h"
#include "google/protobuf/arena.h"
#include "google/protobuf/descriptor.h"
#include "google/protobuf/message.h"

namespace cel {

using ::cel::well_known_types::ValueReflection;

absl::Status NullValue::SerializeTo(
    absl::Nonnull<const google::protobuf::DescriptorPool*> descriptor_pool,
    absl::Nonnull<google::protobuf::MessageFactory*> message_factory,
    absl::Nonnull<absl::Cord*> value) const {
  ABSL_DCHECK(descriptor_pool != nullptr);
  ABSL_DCHECK(message_factory != nullptr);

  google::protobuf::Value message;
  message.set_null_value(google::protobuf::NULL_VALUE);
  if (!message.SerializePartialToString(value)) {
    return absl::UnknownError(
        "failed to serialize message: google.protobuf.Value");
  }
  return absl::OkStatus();
}

absl::Status NullValue::ConvertToJson(
    absl::Nonnull<const google::protobuf::DescriptorPool*> descriptor_pool,
    absl::Nonnull<google::protobuf::MessageFactory*> message_factory,
    absl::Nonnull<google::protobuf::Message*> json) const {
  ABSL_DCHECK(descriptor_pool != nullptr);
  ABSL_DCHECK(message_factory != nullptr);
  ABSL_DCHECK(json != nullptr);
  ABSL_DCHECK_EQ(json->GetDescriptor()->well_known_type(),
                 google::protobuf::Descriptor::WELLKNOWNTYPE_VALUE);

  ValueReflection value_reflection;
  CEL_RETURN_IF_ERROR(value_reflection.Initialize(json->GetDescriptor()));
  value_reflection.SetNullValue(json);
  return absl::OkStatus();
}

absl::Status NullValue::Equal(
    const Value& other,
    absl::Nonnull<const google::protobuf::DescriptorPool*> descriptor_pool,
    absl::Nonnull<google::protobuf::MessageFactory*> message_factory,
    absl::Nonnull<google::protobuf::Arena*> arena, absl::Nonnull<Value*> result) const {
  ABSL_DCHECK(descriptor_pool != nullptr);
  ABSL_DCHECK(message_factory != nullptr);
  ABSL_DCHECK(arena != nullptr);
  ABSL_DCHECK(result != nullptr);

  *result = BoolValue(other.IsNull());
  return absl::OkStatus();
}

}  // namespace cel